Virtual reality systems are computer based systems that provide the experience of acting in a simulated environment that forms a three dimensional virtual world. These systems are used in several different applications such as commercial flight simulators and entertainment systems including computer games and video arcade games. In virtual reality systems a participant typically wears a head-mounted device that enables viewing of a virtual reality world generated by the computer. The system also includes a data entry and manipulation device, such as a pointing device or a specially configured data glove containing sensors and actuators, for interacting with objects in the virtual world. In somewhat sophisticated systems, a full body suit, also containing sensors and actuators, additionally may be provided so that the user can influence and has a realistic feel of objects in the virtual world.
Data entry and manipulation devices for computers, including virtual reality systems, include keyboards, digitizers, computer mice, joysticks, and light pens. One function of these devices, and particularly computer mice and light pens, is to position a cursor on a display screen of a monitor connected to the computer and cause the computer to perform a set of operations, such as invoking a program, which operations are indicated by the location of the cursor on the screen. Once the cursor is at the desired location, buttons on either the mouse or keyboard are depressed to perform the instruction set. However, over time this may become somewhat tedious, since the user must transfer one of their hands from the keyboard to the mouse, move the mouse cursor to the desired location on the screen, then either actuate a button on the mouse, or transfer their hand back to the keyboard and depress buttons to invoke the program.
Alternative means for data entry and manipulation into computers have been provided in the prior art. One increasingly prevalent data entry device comprises a data entry and data manipulation glove, commonly known as "data gloves" and "virtual reality gloves". Data gloves are currently used in several virtual reality related applications ranging from virtual reality entertainment and education systems to medical rehabilitation applications. In a virtual reality system, the data glove is provided to enable the operator to touch and feel objects on a virtual screen and to manipulate the objects.
U.S. Pat. No. 4,988,981, to Zimmerman et al discloses an apparatus and method for generating control signals for manipulating virtual objects in a computer system according to gestures and positions of an operator's hand or other body part. The apparatus includes a glove worn on the hand which includes sensors for detecting the gestures of the hand. The computer system includes circuitry connected to receive gesture signals and hand position signals for generating control signals. The control signals are used to manipulate a graphical representation of the operator's hand which is displayed on a monitor coupled to the computer system. The graphical representations of the operator's hand manipulates virtual objects or tools also displayed by the computer.
U.S. Pat. No. 5,097,252, to Harvill et al., discloses a motion sensor which produces an asymmetrical signal in response to symmetrical movement. In a first embodiment, a plurality of motion sensors are placed over the joints of a hand, with each sensor comprising an optical fiber disposed between a light source and a light sensor. An upper portion of the fiber is treated so that transmission loss of light being communicated through the optical fiber is increased only when the fiber bends in one direction. In another Harvill embodiment, a flexible tube is disposed in close proximity to a finger joint and bends in response to bending of the finger. A light source and light sensor on opposite ends of the tube continuously indicate the extent that the tube is bent.
U.S. Pat. No. 5,429,140, to Burdea et al., is directed to an integrated virtual reality rehabilitation system that employs a force feedback system, such as a force feedback glove to simulate virtual deformable objects. A patient places his or her hand in a sensing glove that measures the force exerted by the patient. Information from the sensing glove is received by an interface and transmitted to a computer where the information can be used to diagnose the patient's manual capability.
The computer then generates rehabilitation control signals for the force feedback glove. The patient places his or her hand in the force feedback glove and attempts to bring the digits together as though grasping the virtual object. The force feedback glove resists the squeezing movement of the digits in a manner that simulates the tactile feel of the virtual object. The force exerted by the fingers of the patient is fed back to the computer control system, where it can be recorded or used to modify rehabilitation control signals.
U.S. Pat. No. 5,612,689, to Lee Jr., discloses a finger articulation controlled information generating system. The Lee system includes a plurality of finger articulation units that individually mount on finger and thumb nails and together, by selected up and down movement of the finger and thumbs, serve as an alternate to a keyboard or other computer interface. Vertical up and down movements of any single one of the ten fingers and various combinations of the fingers is translated into a range of signals recognizable as alphanumeric numbers, digital signaling, word and picture forms, or other symbol forms a user may choose.
However, a disadvantage common to the above noted data gloves is that the gloves are substantially difficult and expensive to manufacture. Difficultly of manufacture is due the plurality of discrete movement monitoring devices provided with the glove for sensing the hand gestures of the wearer. These devices include light emitting sources and appropriate sensing devices. Complex circuitry is needed for the light emitters and coupled sensors and to generate movement indicating control signals.
A further disadvantage of these data gloves is that the movement monitoring devices have poor longevity and are prone to reliability problems. Another disadvantage of these movement monitoring devices is that they may not sufficiently track the hand gestures of the wearer. The sensors may generate signals that are not an accurate representation of the wearer's hand gestures causing erroneous data to be generated. Furthermore, the plurality of sensors located about on the periphery of the gloves, and particularly on the wearer's joints, may substantially inhibit the wearer from moving their hand freely.
Computer generated animation is programmed within the computer to form a cartoon or other animation prior to the animation being run for display. This is similar to a draftsman drawing cells in a cartoon strip. A disadvantage is that it is not possible for a person to have interaction with the computer animation while the animation is being developed or displayed. It would be advantageous to provide a system for interacting with computer animation in "real time"; i.e., wherein a person can interact with the animation while the animation is running.
Thus, there exists a need for a system for manipulating computer generated animation in real time that includes a data management device for a computer which manages data based on hand gestures of an operator.